Module 6 - Mechanical Material Handling
Industrial Regulation - Section 52: When can a worker be supported or transported in a crane, lift truck or similar equipment?
A worker can only be supported or transported in a crane, lift truck or similar equipment when the worker is on a platform and is secured from falling from the equipment.
Industrial Regulation - Section 58: What can an industrial lift truck be left unattended?
An industrial lift truck can not be left unattended unless the forks are in lowered position or solidly supported.
Tower Cranes
Can be set up on ground or within a building, and can be used in an elevator shaft if necessary.
Mobile Cranes
Can have up to 1,000 ton capacity and be as long as 600 feet, not including the mast and boom.
Jib Cranes
Can rotate a load along with lifting and lowering capabilities. The jib crane is supported to a wall in the building and can also be mounted onto a column provided these are strong enough to support the loads based on the approval from a professional engineer.
Industrial Regulation - Section 55: What should exist between the operator's cab and the load if the load is structural steel or logs?
A bulkhead
Screw Conveyors
Move bulk materials on an incline or in a vertical pattern. The material is moved by a chain, and can be also be transported by an attachment such as a movable car. The design of this type of conveyor is one of a continuous spiral belt mounted in a shaft or pipe.
Pneumatic Conveyors
Moves solid objects in the form of granules by using compressed air or a vacuum system in an arrangement of tubes or ducts. You won't find the hazard of moving parts in this type of conveyor, but there is still the hazard of product being released at one end at high velocities.
What can affect crane stability on a constuction site?
On a construction site, one of the hazards that can affect the safety of crane stability is the ground underneath the crane. When a crane is sitting on soft ground or close to the sides of trenches or excavations, this can lead to fatal accidents.
Industrial Regulation - Section 59: When might a crane be overloaded beyond it's maximum rated load?
Only to determine the limit switches for the equipment, but prohibits overloading under normal use.
Deterrent devices
Physical objects to reduce the possibility that a worker will access the danger zone through the use of roller side plates or a guard rail that acts like fencing separating the worker from the conveyor system.
Industrial Regulation - Section 53: What must travelling cranes have?
Required to have stops or bumpers at both ends of the runway.
Industrial Regulation - Section 54: What must a lift truck have in workplaces that are poorly lit?
Requires that a lift truck have head and tail lights
Industrial Regulation - Section 51 (5): What must a lifting device equipped with one or more limit switches have?
Requires that where a lifting device is equipped with one or more limit switches, these must cut off power and apply the brake automatically and not be used as an actual operating control unless they were designed for this. If this is the case, then a second limit switch is required. A limit switch is set by the manufacturer to prevent overloading.
Storage Bridge and Gantry Cranes
Run on rails at ground level. While the gantry crane doesn't travel too far, the storage bridge can cover a span of 300 ft or more. Gantry cranes have devices that move up and down and along the width of the crane and the cranes themselves move front and back along the rails on the ground.
Industrial Regulation - Section 34: What are conveyers that pass over workers required to have?
Section 34 is specific to conveyors and requires that where any conveyor passes over a worker or where there is risk of falling material, guarding is needed beneath the conveyor. There are no standards in Canada specific to conveyor safety.
Industrial Regulation - Section 61: When is there an allowance for gas expansion?
Section 61 also requires an allowance for gas expansion when the ambient temperature increases. This incorporates an understanding of fire safety and properties of gasoline.
Barrier guards
Surround the danger zone and prevent access because of the height of the barrier and the distance from the danger source.
Industrial Regulation - Section 51 (1)(d): What is the lifting device is required to have?
The lifting device is required to have adequate protection for the operator if exposed to falling material. Protection could be a canopy guard, screen, or cab.
Industrial Regulation - Section 51 (1)(c): Where should the load rating be located?
The load rating is required to be clearly visible so that operators are aware of the lifting capabilities of the device.
What is one of the main causes of fatalities in crane operation?
Electrocution
What happens in the event that a crane and hoist operation goes wrong and contact with a power line occurs?
Emergency plan kicks in
A-frame derrick
Gets its name from the shape of the frame. The brace is on a 45 degrees angle to the ground and boom is attached to the arm that extends from the A-frame. The base of this frame must be firmly weighted down.
What is the best way to prevent access to danger zones of conveyers?
Guarding
Apron Conveyor
Have overlapping or interlocking plates that form a continuous moving surface. The apron conveyor can be compared to the tracks of an army tank in terms of the overlapping plates that are linked together.
Industrial Regulation - Section 51 (1)(e): What type of controls do hoists need to have?
Hoists that are powered pneumatically or hydraulically must have controls that return the hoist back to neutral position when released (deadman switch).
Industrial Regulation - Section 57: What must the lift truck must be when the operator leaves the truck unattended?
Immobilized and secured from accidental movement
What types of injuries result from conveyor hazards?
- Contact injuries from transmission parts such as belts and chains. - Crushing of hands and fingers from materials jamming up while being removed. - Falls from workers attempting to cross over conveyors. - Workers who become caught in the moving parts.
Industrial Regulation - Section 56: What must be used when the operator of the crane, or similar equipment, does not have a full view of where they intend on travelling?
A "signaler"
Industrial Regulation - Section 51 (1)(b): Who should be allowed to operate cranes?
A competent person. The "competent person" must thoroughly examine the lifting device to determine whether the device can handle the loads that it is required to lift, and this examination is to happen before the new lifting device is used for the first time, and as often as recommended by the manufacturer, or at least each year. This inspection record must be kept and signed off by the competent person.
Lifting device
A device used to raise or lower material or objects, but does not include an elevating device
Gin Pole and Breast Derricks
A mast with a hoisting tackle, supported by guys on the opposite side of the load. This crane is used for moving loads that only need to be moved a few feet in a horizontal direction.
Stop cord
A metal cable that will stop the conveyor when pulled in either direction. The cable requires very little force when pulled to activate the emergency stop action.
Why are conveyers particularly hazardous?
Conveyors can be particularly hazardous because of the design of the equipment. Conveyors are not always visible to the operator because of their length.
What hazards are associated with conveyers?
Conveyors hazards include: - Pinch points - Falling objects - Accidental starting - Falls on conveyors - Striking against or being struck by conveyors or objects - Jams
What are the common uses of conveyers?
Conveyors provide an efficient way to transport material in the workplace, especially heavy, bulky materials. Conveyors are commonly used: - to move material that is uniform in size and weight, - to move materials continuously form one point to another, - to move materials where the pathway is fixed and does not vary, - when material loads are constant, - when the movement rate is relatively fixed, and/or - to bypass cross traffic, either above or below the working surface.
Why can crane safety be challenging?
Crane safety can be challenging because some of the hazards are directly linked to human behavior; that is to say that operators and workers assisting with, or working in close proximity to cranes, need to exercise good judgment all of the time. Operators should be physically and mentally able to work each shift and meet standards for health that include good vision, depth, and color perception, hearing, coordination, and reaction time.
When are cranes and hoists used?
Cranes and hoists are often used under the following circumstances: - where movement is within a fixed area, - where the movements are intermittent, - when the loads vary in size and weight, - if cross traffic will interfere with alternate methods of material movements such as conveyors, and/or - when loads handled are not uniform.
Chain Conveyors
Designed to haul loads and can pull, push or tow material by connecting to the load through the use of attachments. A chain conveyor can vary in form and use. You will often find the controversial shackle conveyor in poultry processing plants.
Industrial Regulation - Section 51 (1)(a): What do devices require to come up
Device should come with appropriate equipment necessary such as chains, slings, and other fittings.
Portable Conveyors
Flexible and can be formed in many configurations to meet the needs of the workplace design. These conveyors can be found in gravel pits or construction sites and come equipped with large wheels. The conveyor system is often set up on an incline.`
Industrial Regulation - Section 60: What must loads stay clear from coming in contact with?
Live power lines that have enough voltage to seriously injure someone because of electrocution.
Industrial Regulation - Section 51 (4): Where must hoisting controls that are operated from outside of a cab or cage be located?
Located at a safe distance from the load being lifted, and be of a deadman switch type as well.
Gravity Conveyors
Made up of a series of rollers and rely on gravity to move the material. These conveyor systems are affordable and a great option for tasks that don't require a powered conveying system. These were once popular in major grocery stores at one time providing an easy means for grocery transport to a customer's car.
Belt Driven Conveyor
Made up of load rollers, a drive belt, return rollers and an motor. The material is transported along the rollers by the arrangement of mechanical parts that moves the conveyor belt.
Slat Conveyor
Made up of wood or metal slats and functions through chains operating on sprockets. This conveyor usually runs horizontally and can operate on a subtle incline. This type of conveyor will often be used in warehousing operations and commonly used where sorting is performed.
What is used whenever the soil stability is in question.
Timber mats
Overhead Cranes
Travels on a runway and can be operated from the floor or from a cab depending on the design. If the operator must work in a cab, the operator's access to and from the cab should be reviewed to ensure that there are not hazards.
Industrial Regulation - Section 33: What are conveyor systems required to be equipped with?
Under Section 33 of R.R.O Regulation 851 the conveyor system is required to be equipped with automatic start-up warning devices if portions of the conveyor system are not visible from where the operator would stand at the control station. Section 33 does not specify what type of warning device is required, but typical warning devices include both visual and audio warnings such as flashing lights and an alarm sound.
Guy Derricks
Used for lifting structural steel when building tall buildings. By the very nature of design, these cranes manage heavy loads and are required to be secured to steel anchors buried in the ground, with additional weights at the anchor points
Aerial Conveyors
Used often used in construction, mining, and industrial plants to move material from A to B. The conveyor can operate on pneumatic power, manual force, or by chains. The conveyors have a mounted rack and the material being moved hangs on hooks. Because the conveyors are over top of workers, the hazard of falling material is a real concern.
Hoist
Used to raise and lower heavy loads in combination with a crane.
Cranes
Uses a movable arm, often long in length, to raise and lower an object.
